Drive shaft damper

Abstract

A drive shaft damper may be inserted into a hollow automotive drive shaft. The damper includes both foam and a non-foamed retaining member positioned on its outer surface. The foam, which extends above the damper's outer surface, typically possesses a maximum operating temperature of 175° C. or higher.

The invention claimed is: 
     
       1. An NVH-reducing drive shaft damper, comprising:
 a substantially cylindrical structure defining an inner surface and an outer surface; and 
 both (i) foam and (ii) a non-foamed retaining member positioned on the outer surface of said substantially cylindrical structure; 
 wherein said foam has (i) a density of between about 1.0 lb/ft 3  and 3.0 lbs/ft 3 , (ii) an indent-force deflection at 25 percent of between about 28 psi and 36 psi, (iii) a tensile strength of at least about 10 psi, (iv) a tear strength of at least about 1.0 psi, and (v) a minimum elongation of at least about 100 percent. 
 
     
     
       2. The drive shaft damper according to  claim 1 , wherein said substantially cylindrical structure comprises a spirally wound paperboard tube. 
     
     
       3. The drive shaft damper according to  claim 1 , wherein said substantially cylindrical structure comprises a convolute paperboard tube. 
     
     
       4. The drive shaft damper according to  claim 1 , wherein said foam possesses a maximum operating temperature of at least about 350° F. 
     
     
       5. The drive shaft damper according to  claim 1 , wherein said foam possesses a maximum operating temperature of at least about 425° F. 
     
     
       6. The drive shaft damper according to  claim 1 , wherein said foam possesses a maximum operating temperature of at least about 500° F. 
     
     
       7. The drive shaft damper according to  claim 1 , wherein said foam comprises silicone-containing polymeric material. 
     
     
       8. The drive shaft damper according to  claim 1 , wherein said foam comprises an elastomeric foam. 
     
     
       9. The drive shaft damper according to  claim 1 , wherein said foam comprises a polyether foam. 
     
     
       10. The drive shaft damper according to  claim 1 , wherein said foam possesses a substantially constant thickness. 
     
     
       11. The drive shaft damper according to  claim 1 , wherein said foam is positioned on the outer surface of said substantially cylindrical structure to substantially cover the remaining outer surface of said substantially cylindrical structure not covered by said non-foamed retaining member. 
     
     
       12. The drive shaft damper according to  claim 1 , wherein said foam extends above the outer surface of said substantially cylindrical structure and has an uncompressed thickness of between about 0.25 inch and 2.0 inches. 
     
     
       13. A dampened drive shaft possessing NVH-reduction, comprising (i) a tubular drive shaft defining an internal annular space and (ii) the drive shaft damper according to  claim 1  compressively positioned and frictionally fixed within said tubular drive shaft. 
     
     
       14. An NVH-reducing drive shaft damper, comprising:
 a substantially cylindrical paperboard structure defining an inner surface and an outer surface; 
 a non-foamed retaining member secured to the outer surface of said substantially cylindrical paperboard structure, wherein said non-foamed retaining member extends above the outer surface of said substantially cylindrical paperboard structure; and 
 foam applied to the outer surface of said substantially cylindrical paperboard structure to substantially cover the remaining outer surface of said substantially cylindrical paperboard structure not covered by said non-foamed retaining member, wherein said foam extends above the outer surface of said substantially cylindrical paperboard structure and has an uncompressed thickness of between 0.25 inch and 2.0 inches; 
 wherein said foam is a polyether foam having (i) a density of between 1.0 lb/ft 3  and 3.0 lbs/ft 3 , (ii) an indent-force deflection at 25 percent of between 28 psi and 36 psi, (iii) a tensile strength of at least 10 psi, (iv) a tear strength of at least 1.0 psi, (v) a minimum elongation of at least 100 percent, and (vi) a substantially constant thickness. 
 
     
     
       15. The drive shaft damper according to  claim 14 , wherein said substantially cylindrical paperboard structure comprises substantially smooth paperboard that defines the outer surface of said substantially cylindrical paperboard structure. 
     
     
       16. The drive shaft damper according to  claim 14 , wherein said substantially cylindrical paperboard structure comprises at least one single-faced corrugated paperboard ply. 
     
     
       17. The drive shaft damper according to  claim 14 , wherein said polyether foam comprises a charcoal polyether foam having a density of between about 1.05 lbs/ft 3  and 1.15 lbs/ft 3 . 
     
     
       18. The drive shaft damper according to  claim 14 , wherein:
 said non-foamed retaining member is a rubber retaining member that is spirally wound around said substantially cylindrical paperboard structure; and 
 said substantially cylindrical paperboard structure comprises a spirally wound paperboard tube or a convolute paperboard tube. 
 
     
     
       19. A dampened drive shaft possessing NVH-reduction, comprising (i) a tubular drive shaft defining an internal annular space and (ii) the drive shaft damper according to  claim 18  compressively positioned and frictionally fixed within said tubular drive shaft. 
     
     
       20. A dampened drive shaft possessing NVH-reduction, comprising (i) a tubular drive shaft defining an internal annular space and (ii) the drive shaft damper according to  claim 14  compressively positioned and frictionally fixed within said tubular drive shaft.